const { test } = require('node:test');
const assert = require('node:assert');
const fs = require('node:fs');
const path = require('node:path');

const des = require('des.js');
global.des = des;

const html = fs.readFileSync(path.join(__dirname, '..', 'index.html'), 'utf8');

function extractFunc(src, name) {
	const re = new RegExp('function\\s+' + name + '\\s*\\([^)]*\\)\\s*\\{');
	const m = re.exec(src);
	if (!m) throw new Error('function ' + name + ' not found');
	let i = m.index + m[0].length - 1;
	let depth = 0;
	for (; i < src.length; i++) {
		if (src[i] === '{') depth++;
		else if (src[i] === '}') {
			depth--;
			if (depth === 0) break;
		}
	}
	return src.slice(m.index, i + 1);
}

const FNS = ['hexToBytes', 'bytesToHex', 'des3Keys', 'des3EncryptBlock', 'des3CbcEncrypt',
	'xorBytes', 'zeroPad', 'cbcMac', 'genSp'];
let code = '';
for (const f of FNS) code += extractFunc(html, f) + '\n';

// All test vectors are computed with the synthetic dummy key material below
// (no live/sample card keys, no ICCIDs). They are cross-checked byte-for-byte
// against pySim's OtaDialectSms.encode_cmd reference implementation.
const K = '00112233445566778899AABBCCDDEEFF';

const DEFAULTS = {
	'sp-apdu': '00A40000023F00',
	'sp-spi1': '06',
	'sp-spi2-hex': '09',
	'sp-kic-hex': '15',
	'sp-kid-hex': '15',
	'sp-tar': 'B00000',
	'sp-cntr': '0000000001',
	'sp-kic-key': K,
	'sp-kid-key': K,
	'sp-padding': '00',
};

const values = {};
const elements = {};
global.document = {
	getElementById(id) {
		if (!elements[id]) elements[id] = { value: values[id] || '' };
		return elements[id];
	},
};

eval(code);

function run() {
	genSp();
	return (elements['sp-result'] || { value: '' }).value;
}

function makeRun(overrides) {
	for (const [id, v] of Object.entries(DEFAULTS)) {
		values[id] = v;
		if (elements[id]) elements[id].value = v;
	}
	for (const [id, v] of Object.entries(overrides || {})) {
		values[id] = v;
		if (elements[id]) elements[id].value = v;
	}
	return run();
}

test('ciphered + CC SPI 06/09', () => {
	assert.strictEqual(
		makeRun({}),
		'00201506091515B00000C08F58C38860ACB3A362FFFE670AD13759A2A6B4C1A91116');
});

test('ciphered + CC SPI 16/01 (counter_must_be_higher, plaintext PoR)', () => {
	assert.strictEqual(
		makeRun({ 'sp-spi1': '16', 'sp-spi2-hex': '01' }),
		'00201516011515B00000E42573469E68A8462A57A505B0E2B1C09C1928C7A182311F');
});

test('unciphered + CC SPI 02/09', () => {
	assert.strictEqual(
		makeRun({ 'sp-spi1': '02', 'sp-spi2-hex': '09' }),
		'001D1502091515B0000000000000010085A8CA1A9828B0BB00A40000023F00');
});

test('unciphered packet uses CPL = octets from CHL to end (0x001d)', () => {
	const out = makeRun({ 'sp-spi1': '02', 'sp-spi2-hex': '09' });
	assert.strictEqual(out.slice(0, 4), '001D');
	assert.strictEqual(out.length, 62);
});

test('sysmocom public reference vector (spi1 04 / spi2 19, cntr=0)', () => {
	assert.strictEqual(
		makeRun({
			'sp-spi1': '04',
			'sp-spi2-hex': '19',
			'sp-kic-hex': '35',
			'sp-kid-hex': '35',
			'sp-cntr': '0000000000',
			'sp-kic-key': 'C21DD66ACAC13CB3BC8B331B24AFB57B',
			'sp-kid-key': '12110C78E678C25408233076AA033615',
		}),
		'00180D04193535B00000E3EC80A849B554421276AF3883927C20');
});

test('missing APDU reports an error', () => {
	assert.strictEqual(makeRun({ 'sp-apdu': '' }), 'Error: specify APDU');
});

test('cbcMac known answer (synthetic key)', () => {
	const input = hexToBytes('001d1502091515b0000000000000010000a40000023f00');
	assert.strictEqual(bytesToHex(cbcMac(input, hexToBytes(K))), '85A8CA1A9828B0BB');
});